Apparatus for the treatment of particulate solids

ABSTRACT

Apparatus for the treatment of particulate solids comprises a vessel disposed with its longitudinal axis in a horizontal or inclined direction and adapted to receive the material to be treated at one end for discharge at the other end after passage therethrough, the vessel having a longitudinally extending inwardly directed protuberance in its lower part and being mounted for oscillatory movement about a longitudinally extending axis and means for effecting said movement whereby material passing through the vessel is repeatedly transferred from sideto-side of said inwardly directed protuberance.

United States Patent Grieve [54] APPARATUS FOR THE TREATMENT OF PARTICULATE SOLIDS [72] Inventor: Alan Grieve, Bramhall, England [73] Assignee: Simon-Carvos Limited, Cheshire, England [22] Filed: Nov. 5, 1970 [21] Appl. No.2 87,051

[30] Foreign Application Priority Data Nov. 18, 1969 Great Britain ..56,296/69 [52] U.S.Cl ..259/2, 259/75 [51] int. Cl. ..B01i 13/00 [58] Field ofSearch ..259/3,13,29,75,l73,14, 259/30, 81 R, 89, 175, 176, 177 R, 80, 2, 56;

[56] References Cited UNITED STATES PATENTS 1,382,421 10/1932 neq icl 329333 5 u 51 Feb. 22, 1972 2,315,229 3/1943" Schieferstein ..241/17ox 2,764,393 9/1956 Fisher ..259/81RX FOREIGN PATENTS OR APPLICATIONS 629,027 9/1949 Great Britain ..68/210 Primary Examiner-Walter A. Scheel Assistant Examiner-Philip R. Coe Attorney-Norris & Bateman [57] ABSTRACT Apparatus for the treatment of particulate solids comprises a vessel disposed with its longitudinal axis in a horizontal or inclined direction and adapted to receive the material to be treated at one end for discharge at the other end after passage therethrough, the vessel having a longitudinally extending in- .wardly directed protuberance in its lower part and being :mounted for oscillatory movement about a longitudinally extending axis and means for effecting said movement whereby material passing through the vessel is repeatedly transferred from side-to-side of said inwardly directed protuberance.

11 Claims, 5 Drawing Figures PATENTEUFEB 22 I972 IN VI NTOR ALAN QRIEVE APPARATUS FOR THE TREATMENT OF PARTICULATE SOLIDS This invention concerns apparatus for the treatment of particulate solids, being apparatus of the kind (hereinafter termed of the kind referred to) comprising a vessel disposed with its longitudinal axis in a horizontal or inclined direction and adapted to receive the material to be treated at one end for discharge at the other end after passage therethrough.

Apparatus of the kind referred to comprising a vessel of generally cylindrical shape and adapted to be rotated about its central longitudinal axis is well known and widely used for effecting many different operations such as mixing, cooling, drying, calcining and high-temperature chemical reactions typified by the production of cement clinker or the reduction of iron oxides for example. Well-known variations on a simple cylindrical shape include the provision of weir plates and/or lifting blades, the use of sections of different diameters and the trommel type in which the diameter increases progressively from inlet to outlet. These variations are designed to improve mixing, to control retention time or to increase gas-solid contact and consequently heat transfer. Particularly when treating large tonnages, rotary units may be very long as in the cement industry where kilns of 400 to 500 ft. in length are not uncommon. Such length is largely dictated by the need to restrict the percentage fill of the kiln cross section. In a simple cylindrical vessel if the percentage full exceeds about percent it is found that a part of the charge flows inertly through the kiln without contacting either the walls of the kiln or the gases passing through it. In mixing operations a somewhat higher degree of fill is permissible particularly if lifting blades are fitted, but in general the limit here is around l2 to percent, and such lifting blades are not practicable on vessels operating at high temperatures.

It is an object of the present invention to provide apparatus of the kind referred to which permits a higher degree of fill, and consequently a smaller vessel size for a given throughput, while ensuring that all the feed material is subject to the same conditions during its passage through the vessel.

According to the present invention apparatus for the treatment of particulate solids comprises a vessel disposed with its longitudinal axis in a horizontal or inclined direction and adapted to receive the material to be treated at one end for discharge at the other end after passage therethrough, the vessel having a longitudinally extending inwardly directed protuberance in its lower part and being mounted for oscillatory movement about a longitudinally extending axis and means for effecting said movement whereby material passing through the vessel is repeatedly transferred from side to side of said inwardly directed protuberance.

The invention will be further apparent from the following description with reference to the figures of the accompanying drawing which show, by way of example only, a number of forms of apparatus embodying the invention.

Of the drawing:

FIG. 1 shows a partially sectioned side elevation of one form of apparatus;

FIG. 2 shows a cross section of the apparatus on the line llll ofFlG. 1; and

FIGS. 3, 4 and 5 show cross sections of modified forms of apparatus.

Referring firstly to FIGS. 1 and 2 it will be seen that the apparatus essentially comprises a cylindrical vessel 10 which is mounted with its longitudinal central axis in an inclined direction. Material to be treated is introduced into the vessel at the upper end thereof by means of a feed chute 11 for discharge at the lower end into a collection chute 12 after passage therethrough. As can clearly be seen from the drawings the circularity of the cross section of the vessel 10 is interrupted in the lower segment by an inwardly protruding wedge member 13 which extends over a substantial portion of the length of the vessel 10, terminating at its two ends in slightly spaced relationship from the end walls of the vessel.

The vessel 10 is supported for rotational movement by rollers 14 mounted for free rotation in brackets 15 carried by a supporting base structure 16. The rollers 14 engage with rail members 17 extending around the periphery of the vessel 10 at spaced locations.

A toothed rack 18 extends around the periphery of the vessel 10 and is engaged by pinions 19 adapted to be driven by electric motors 20.

Control means are provided for the electric motors so that the pinions are driven alternately, first in one direction and then in the other, so that the vessel 10 is caused to oscillate about its longitudinal central axis. Preferably the vessel is caused to oscillate through a suitable angle from the vertical of between 45 and to either side. The exact angle of oscillation should be matched to the angle of the protruding wedge section 13 and to the characteristics of the material being treated, so that at each point of maximum displacement all of the material lifted by the protruding section slides therefrom. In this way the material is continuously moved from side to side of the protruding section. It will be understood that as the material moves from one side of the wedge to the other, the material which was at the top on one side of the wedge is transferred to the bottom on the other side of the wedge with the result that there is a very efficient turning over and consequent mixing of the material.

We have found that by utilizing an arrangement as described the percentage fill of the vessel can be considerably increased to around 20 to 30 percent while ensuring that all of the feed material is subjected to the same conditions during its passage through the vessel.

The vessel will normally be operated in conjunction with ancillary equipment determined by the nature of the process to be carried out on the material passing through the vessel.

Thus, there may be means for passing treatment gases through the interior of the vessel either cocurrently or countercurrently with the material being treated. The gases may be either cold for cooling operations or heated if the material is to be subjected to a heat treatment.

In certain high-temperature operations burners for a suitable liquid or gaseous fuel may be mounted within the vessel or externally of the vessel. Again, for example, for cooling operations the lower portion of the vessel may be mounted so as to be immersed in a bath of cooling water.

The inner lining of the vessel can be designed in two parts, the lower one of which is subjected to contact with both solids and gases while the upper part is in contact with gases only. This makes the selection of the most appropriate material for each lining more simple.

The protruding wedge section also imparts longitudinal rigidity to the vessel to overcome the risk of distortion or bending at high temperatures in the absence of continuous rotation.

in particular applications the protruding section could also serve as a means for introducing or removing gases through suitably designed ports at a point or points along the length of the vessel. Gases could also be addedor extracted through ports in the upper part of the vessel with flexible connections if required.

It will be appreciated that it is not intended to limit the invention to the above example only, many variations, such as might readily occur to one skilled in the art, being possible without departing from the scope thereof.

As with more conventional vessels weir plates could be fitted on either side of the protruding section in order to control the percentage fill and the retention of material.

The upper portion of the profile of the vessel may be enlarged so as to provide increased cross-sectional area as shown in FIG. 3 to limit the velocity of gases passing through the vessel either cocurrently or concurrently with the flow of solids. Where gases are not involved as in the operations of mixing for example this upper part could be flat or could be removed altogether as shown in FIG. 4, when the vessel is essentially of troughlike form.

The protruding section need not be of wedge shape, and could for example be of part-circular section as indicated in FlG. 5.

What is claimed is:

1. Apparatus for the treatment of particulate solids comprising a vessel disposed with its longitudinal axis in a horizontal or inclined direction and adapted to receive the material to be treated at one end for discharge at the other end after passage therethrough, the vessel having a longitudinally extending inwardly directed protuberance in its lower part and being mounted for oscillatory movement about a longitudinally extending axis and means for effecting said movement whereby material passing through the vessel is repeatedly transferred from side to side of said inwardly directed protuberance.

2. Apparatus according to claim 1 wherein said inwardly directed protuberance is of wedge-shaped form.

3. Apparatus according to claim 1 wherein said inwardly directed protuberance is of part-circular section.

4. Apparatus according to claim 1 wherein the vessel is adapted to be oscillated through an angle from the vertical of between 45 and 135 to either side.

5. Apparatus according to claim 4 wherein the vessel is supported on rollers which engage with rails of circular form secured to the peripheral surface of the vessel.

6. Apparatus according to claim 5 including a toothed rack of circular form secured to the peripheral surface of the vessel, at least one pinion engaging with said rack and adapted to be driven alternately, first in one direction and then in the other so that the vessel can be caused to oscillate.

7. Apparatus according to claim 1 wherein the vessel is supported on rollers which engage with rails of circular form secured to the peripheral surface of the vessel.

8. Apparatus according to claim 7 including a toothed rack of circular form secured to the peripheral surface of the vessel, at least one pinion engaging with said rack and adapted to be driven al2temately, first in one direction and then in the other so that the vessel can be caused to oscillate.

9. Apparatus according to claim 1 wherein the vessel is of circular cross section.

10. Apparatus according to claim 1 wherein the cross section of the vessel is of circular form at the lower part and of noncircular form at the upper part giving increased cross-sectional area at the upper part relative to the lower part.

11. Apparatus according to claim 1 wherein the vessel is in the form of a trough having an open top. 

1. Apparatus for the treatment of particulate solids comprising a vessel disposed with its longitudinal axis in a horizontal or inclined direction and adapted to receive the material to be treated at one end for discharge at the other end after passage therethrough, the vessel having a longitudinally extending inwardly directed protuberance in its lower part and being mounted for oscillatory movement about a longitudinally extending axis and means for effecting said movement whereby material passing through the vessel is repeatedly transferred from side to side of said inwardly directed protuberance.
 2. Apparatus according to claim 1 wherein said inwardly directed protuberance is of wedge-shaped form.
 3. Apparatus according to claim 1 wherein said inwardly directed protuberance is of part-circular section.
 4. Apparatus according to claim 1 wherein the vessel is adapted to be oscillated through an angle from the vertical of between 45* and 135* to either side.
 5. Apparatus according to claim 4 wherein the vessel is supported on rollers which engage with rails of circular form secured to the peripheral surface of the vessel.
 6. Apparatus according to claim 5 including a toothed rack of circular form secured to the peripheral surface of the vessel, at least one pinion engaging with said rack and adapted to be driven alternately, first in one direction and then in the other so that the vessel can be caused to oscillate.
 7. Apparatus according to claim 1 wherein the vessel is supported on rollers which engage with rails of circular form secured to the peripheral surface of the vessel.
 8. Apparatus according to claim 7 including a toothed rack of circular form secured to the peripheral surface of the vessel, at least one pinion engaging with said rack and adapted to be driven alternately, first in one direction and then in the other so that the vessel can be caused to oscillate.
 9. Apparatus according to claim 1 wherein the vessel is of circular cross section.
 10. Apparatus according to claim 1 wherein the cross section of the vessel is of circular form at the lower part and of noncircular form at the upper part giving increased cross-sectional area at the upper part relative to the lower part.
 11. Apparatus according to claim 1 wherein the vessel is in the form of a trough havinG an open top. 